OpenWrt 18.06 RC2 Dmesg message (urandom, lack of entropy)

Lack of entropy is a real problem in embedded devices right after boot.

I think that the warning for urandom quality was added to the kernel some time ago, but the warning was modified just a few months ago: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit/?h=v4.14.56&id=4e00b339e264802851aff8e73cde7d24b57b18ce and backport to 4.9: https://lkml.org/lkml/2018/4/30/895

You might read Randomness quality for some background on lack of entropy in Openwrt. I wrote there a brief summary of mitigation attempts in Openwrt in the last 5-6 years.

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